Synthetic resins and method of preparing the same



Patented Mar. 31, 1936' 2,036,009

SYNTHETIC RESINS AND METHOD OF PREPARING THE SAME James G. E. Wright, Alplaus, N. Y., assignor to General Electric Company, a corporation of New York No Drawing. Application July 21, 1931, Serial No. 552,292

4 Claims. 106-22) The present invention relates to synthetic res- I have made the discovery that I can utilize ins and to a method of preparing the same. alkyd resins, and moreparticularly those alkyd More specifically this invention is concerned with resins which are flexible in character, to replace the production of a synthetic resin which is acid, the vinyl acetate ingredient in the resin above 5 alkali, water and flame-proof, which is moldable, referred to. I have found that such resins are 5' capable of being cured, and which can be made compatible with the polymerized vinyl chloride, as a product of any desired degree of plasticity can be easily and successfully compounded thereand flexibility. with by an exceedingly simple procedure to yield Vinyl compounds have heretofore been utia product which embodies all the properties and lized in the preparation of synthetic resins. For advantages of the polymerized vinyl chloride enu- 10 example, one well known resin of this type is merated above and in addition surprisingly gives prepared by first dissolving polymerized vinyl a product which is easily heat convertible to the acetate in a solvent such as toluol. Vinyl chloinfusible state, particularly where a small amount ride, which is a gas under ordinary conditions, of a catalyst such as zinc oxide is added. Moreis conducted into this solution and maintained over the expensive vinyl acetate is in this man- 15 therein under pressure. Under the influence of ner replaced by a cheaper and for many purheat, light and an oxidizing catalyst, for examposes, a better material. ple, benzoyl peroxide, the vinyl chloride poly- Asis well known, alkyd resins include all those merizes and associates itself in intimate relacomplexes resulting primarily from the intertionship with already polymerized vinyl acetate. reaction oi a polyhydric alcohol, such as glycerine, 20 The'excess solvent is distilled off and a resinous with a polybasic acid, such as phthalic acid or product remains which is readily moldable. its anhydride, with or without other reacting in- In the resin above described the vinyl chloride gredients. usually preponderates over the vinyl acetate, the In order that my invention may-be more fully ratio being ordinarily 4 t0 The vinyl o de understood and practiced by those skilled in the 25 ingredient in the resin is acid, alkali, water and art to which it pertains, the following illustrative flame-proof, but is not very plastic by itself, examples are given:

For example, when an attempt is made to sheet it on ordinary rubber compounding rolls it be- Example I haves pretty much like dry gelatin. The vinyl Per cent by Weight 30 acetate ingredient is, on the other hand, very Ingredients plastic and adhesive to e l and Othel; Polymerized vinyl chloride 40 tances, but is not at all water resist nt- T Alkyd resin 1o compounded ingredients, in the prop i above Dibutyl phthalate 30 noted and prepared as outlined, ive a resin Alpha, cellulose 7.5' 35 bodying the desirable properties o e ingredi- Titanium oxide pigment 12.5 cut and a product which is thermoplastic in character, This thermoplastic resin is one whi h Tota1 100 0 has l s shrinkage in the mold than any other n 40 known moldable synthetic resin. 40

The most expensive ingredient in the above An alkyd ream was first prepared by reacting resin is the polymerized vinyl acetate. It has Per cent by weight long been desired to replace this ingredient with Glycerine 17 6 a cheaper al which would be compatible Phthahc g a 42 5 45 with the vinyl chloride and yield a resin having 7 45 the desirable properties of the above mentioned fig g z i i resin. Again, because of the fact that the resin is thermoplastic in character it has not been The resin ingredients are cooked in a suitable possible in many cases to utilize in a practical vessel, for example an aluminum container, to way the other desirable properties of the resin a 30 second cure at 200 C. The mass is poured 50 since, as is well known, a resin which cannot be into an amalgamated pan to a thickness of apcured to the iniusible state and which softens proximately A inch. The resin then is cured again on heating, although hard when cold or for about 22 hours at a temperature of approxiat room temperature, is limited in many indusmately 150 C., the sheet being turned over at trial and technical applications. the end 01 11 hours to expose the under side. 55

The resin is now in the so-called B-stage or semicured stage. The resin is one containing a 1:2 ratio of polyhydric alcohol-polybasic acid ester to dihydric alcohol-dibasic aliphatic acid ester, that is, glycerol phthalate to glycol adipate and is quite flexible in nature.

This alkyd resin is milled with the other ingredients above mentioned on an ordinary type of rubber compounding rolls for about hour at a temperature of about 95 C. It can then be molded in the ordinary type of. hydraulic press utilizing a temperature range of approximately to C. and a pressure range of 300-2500 pounds per square inch. The molded productv may becured to the infusible state outside of the mold employing a temperature range of approximately 80 to C. for a time up to approximately 22 hours. I

The molded product prepared as described in this example is flexible. It molded easily, did not stick to the mold, and took sharp impressions.

Example II Ingredients Per cent by weight Alkyd resin; 57.1 Polymerized vinyl chloride 14.2 Alpha cellulose 11.0 Titanium oxide pigment 17.7

The alkyd resin is prepared as outlined in ExampleI. The molded product, uncured, was exceedingly flexible in character, and pliable like soft rubber.

The alkyd resin in this example may be prepared as in Example I and compounded in the same manner with the other ingredients. The molded product took sharp impressions and did not stick to the mold. It had a glass-like surface. The molded product was cured outside of th mold and held its shape excellently. 1

Example IV Ingredients Per cent by weight Alkyd resin 42.5 Alpha cellulose 10.7 Titanox B 42.5 Polymerized vinyl chloride 4.3

In this example the alkyd resin may be prepared as in Example I, but the ratio of ingredients is so chosen that the ratio of glycerol phthalate to glycol adipate is 1:6 instead of1:2, as in Example I. The compounding of the ingredients is carried out as in that example. The molded product in this case is soft and pliable like rubber as the product in Example II. It retains its flexibility at low temperatures (about 12 0.), and even when not cured has excellent water resistance.

The above examples clearly illustrate the invention but it is apparent that the ingredients and proportions thereof may be varied. For example, the alkyd resin may be one other than that specifically mentioned in the examples.

That is, other polybasic acids besides phthalic acid or its anhydride and polyhydric alcohols other than glycerine, especially those having three or more hydroxyl groups in the molecule, may be employed in making the alkyd resin.

Within the scope of the present invention is also included alkyd resins prepared by reacting the resin'ingredients in the presence of vegetable oils. such as the drying or semi-drying oils and/or the acids derived therefrom. In making the flexible type of alkyd resin dihydrlc alcohols other than ethylene glycol may be used, for example, propylene glycol, diethylene glycol, tetramethylene glycol and the like; and thedibasic aliphatic acid need not be adipic acid, it may be such an acid as succinic, malic, maleic, fumaric, glutaric, pir'nelic, azelaic, suberic acid and the like, or a suitable combination of these acids. By varying the ratio of polyhydric alcohol-polybasic acid ester to the dihydric alcohol-dibasic aliphatic acid ester in theflexible type of alkyd resin various degrees of "toughness and flexibility can be obtained in the finished resin.

It is of course understood that fillers other than alpha cellulose and diatomaceous earth may be used, these being merely representative of any number of suitable fillers available and which will readily suggest themselves'to those skilled in the art.

Suitable equivalents of polymerized vinyl chloride may of course be employed and are tdeemed within the scope .of the present invenion.

What I claim as new and desire to secure by Letters Patent of the United States is:--

1. A resinous composition capable of being cured to the infusible state which comprises polymerized vinyl chloride and a semi-cured alkyd resin which is the product of reaction of glycerine, phigialic anhydride, ethylene glycol and adipic aci 2. A resinous composition capable of being cured to the infusible state which comprises a polymerized vinyl halide and a semi-cured alkyd resin which is the product of reaction of a polyhydric alcohol, a polybasic organic acid, a diresinous composition of claim 1.

4. An article comprising essentially the cured resinous composition of claim 2.

JAMES G. E. WRIGHT. 

